A variety of underwater, diving masks have been used for many years in such activities as scuba diving or skin diving. The typical mask includes a rigid frame that supports a window or lens through which the diver may view his or her surroundings. A flexible skirt is also mounted to the frame and includes an edge designed to fit along the face of the diver. Typically, the skirt extends along the forehead, around the outside of the eyes and under the nose of the diver to prevent water from entering the space between the lens and the diver's eyes.
The mask is held against the diver's face in this sealing relationship by an elastomeric strap that extends about the back of the diver's head. Many modern masks have a silicone skirt that seals against the diver's face with minimal pressure. However, the mask strap is preferably adjustable to facilitate this sealing engagement with the diver's face without causing undue force against the diver's face or other discomfort. Most mask straps are adjustably mounted to the mask through a buckle assembly. Typically, the strap has a plurality of ridges that interact with a catch to allow the diver to adjust the length of the mask strap.
In certain conventional masks, the buckle assembly is affixed to the frame and includes a roller mounted on a pin. The mask strap extends through the buckle, wraps around the roller and doubles back on itself with the ridges extending outwardly. A spring-loaded catch is pivotably mounted within the frame to interact with a select ridge and hold the mask strap in place against the roller. If the length of the strap must be adjusted, the catch is simply pivoted against the force of the spring to release its engagement with the strap. The length of the strap is then adjusted to a desired length and the catch released. The spring pivots the catch back into engagement with the next selected ridge and holds the strap at that desired length.
This affixed buckle arrangement can be problematic when the diver wants to adjust the orientation of the mask strap about his or her head. Because the buckle does not pivot upwardly or downwardly with respect to the diver's head, the strap must generally be placed about the diver's head in one orientation. The diver may be able to move the strap upwardly or downwardly along the back of his or her head, but this is often less comfortable or less stable i.e. the strap is biased back towards a position in general alignment with the orientation of the buckle.
Attempts have been made to overcome this problem by constructing buckles that are pivotal. This allows the orientation of the mask strap to be adjusted with respect to the mask and the diver's head. For example, some divers may find it more comfortable to orient the mask strap at a slight upward angle and others may find it more comfortable to orient the mask strap at a somewhat downward angle rather than the conventional orientation that is substantially perpendicular to the lens of the mask.
Generally, the pivotal buckles include a plate pivotally mounted within a slot located within the frame of the mask. A roller is mounted at the opposite end of the plate to permit the strap to extend thereabout. A catch is pivotably mounted to the plate via a living hinge and interacts with ridges on the strap to maintain the strap in position. Thus, this type of buckle does not have the positive action of a spring loaded catch to pivot the catch into cooperation with the ridges on the strap. Additionally, the resiliency of the living hinge tends to decline over time with repeated usage.
It would be advantageous to design a pivotal buckle that utilized more dependable components and made possible the use of a spring loaded hinge.